$vbulletin->datastore->fetch(array('customname')) adds 1 extra database call

[kh99]

Well, you won't be able to use the data in the init_startup hook because it hasn't been loaded yet, it's just adding your field to the array of fields to be loaded. But if you check $vbulletin->customname somewhere after the init_startup hook has executed (just about any other hook location since init_startup is first), you should find that it works.